{"id":{"repo_id":"dundee","oai_identifier":"oai:discovery.dundee.ac.uk:studenttheses/f41bf6b9-ae59-4a41-ba29-d5873821418b"},"canonical_url":"https://search.dev.ndltd.org/etd/dundee/oai:discovery.dundee.ac.uk:studenttheses/f41bf6b9-ae59-4a41-ba29-d5873821418b","repository":{"repo_id":"dundee","name":"University of Dundee","base_url":"https://discovery.dundee.ac.uk/ws/oai"},"display":{"title":"Cavitation in focused ultrasound","abstract":"A novel experimental configuration is developed combining a high intensity
focused ultrasound source and a pulsed-laser, for the study
of cavitation in a field typical of those used for therapeutic ultrasound.
The sonoptic chamber is specifically designed to avoid the formation
of acoustic standing waves, known to have a critical influence
on cavitation behaviour. A new technique of laser-nucleated acous-
tic cavitation is presented, whereby a laser-pulse of energy below the
breakdown threshold for the host medium, acts to nucleate acoustic
cavitation in a pre-established field. This facilitates the incorporation
of high-speed cameras for interrogation at unprecedented temporal
and spatial resolution, combined with acoustic detection directly correlated
to the observed cavitation activity. A number of cavitation
phenomena are investigated, including bubble-ensemble oscillations at
a very early stage of development, in response to the acoustic driving.
The frequency of oscillation, which bifurcates with increasing intensity,
is also detected in the acoustic emissions. The application of
a single-bubble model predicts a source for the acoustic emissions of
quiescent radius equivalent to the bubble-ensemble observed, for each
intensity investigated. The physical translation of the ensemble, due
to the radiation force imposed by the primary field, is also analysed.
For laser-pulses of energy above the breakdown threshold, applying
focused ultrasound to the cavity promotes and actuates jet-formation.
The characteristics of the so formed jets depend on the intensity and
location of the cavity relative to the ultrasound focus.","abstract_html":"A novel experimental configuration is developed combining a high intensity<br/>focused ultrasound source and a pulsed-laser, for the study<br/>of cavitation in a field typical of those used for therapeutic ultrasound.<br/>The sonoptic chamber is specifically designed to avoid the formation<br/>of acoustic standing waves, known to have a critical influence<br/>on cavitation behaviour. A new technique of laser-nucleated acous-<br/>tic cavitation is presented, whereby a laser-pulse of energy below the<br/>breakdown threshold for the host medium, acts to nucleate acoustic<br/>cavitation in a pre-established field. This facilitates the incorporation<br/>of high-speed cameras for interrogation at unprecedented temporal<br/>and spatial resolution, combined with acoustic detection directly correlated<br/>to the observed cavitation activity. A number of cavitation<br/>phenomena are investigated, including bubble-ensemble oscillations at<br/>a very early stage of development, in response to the acoustic driving.<br/>The frequency of oscillation, which bifurcates with increasing intensity,<br/>is also detected in the acoustic emissions. The application of<br/>a single-bubble model predicts a source for the acoustic emissions of<br/>quiescent radius equivalent to the bubble-ensemble observed, for each<br/>intensity investigated. The physical translation of the ensemble, due<br/>to the radiation force imposed by the primary field, is also analysed.<br/>For laser-pulses of energy above the breakdown threshold, applying<br/>focused ultrasound to the cavity promotes and actuates jet-formation.<br/>The characteristics of the so formed jets depend on the intensity and<br/>location of the cavity relative to the ultrasound focus.","abstract_has_math":false,"creators":["Gerold, Bjoern"],"institution":"University of Dundee","degree_name":"Doctor of Philosophy","degree_level":"Doctoral Thesis","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013","date_published":"2013","updated_at":"2026-07-24T02:07:46Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["oai:discovery.dundee.ac.uk:studenttheses/f41bf6b9-ae59-4a41-ba29-d5873821418b"],"render_values":[{"text":"oai:discovery.dundee.ac.uk:studenttheses/f41bf6b9-ae59-4a41-ba29-d5873821418b","href":null,"code":true}]}]},"links":{"outbound_url":"https://discovery.dundee.ac.uk/en/studentTheses/f41bf6b9-ae59-4a41-ba29-d5873821418b","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Gerold, Bjoern"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2013"]},{"key":"dc:date.issued","label":"Date","values":["2013"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["University of Dundee"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Dundee"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://discovery.dundee.ac.uk/en/studentTheses/f41bf6b9-ae59-4a41-ba29-d5873821418b"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral Thesis"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["Doctor of Philosophy"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["oai:discovery.dundee.ac.uk:studenttheses/f41bf6b9-ae59-4a41-ba29-d5873821418b","https://discovery.dundee.ac.uk/en/studentTheses/f41bf6b9-ae59-4a41-ba29-d5873821418b"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://discovery.dundee.ac.uk/files/2189740/Gerold_phd_2013.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["A novel experimental configuration is developed combining a high intensity
focused ultrasound source and a pulsed-laser, for the study
of cavitation in a field typical of those used for therapeutic ultrasound.
The sonoptic chamber is specifically designed to avoid the formation
of acoustic standing waves, known to have a critical influence
on cavitation behaviour. A new technique of laser-nucleated acous-
tic cavitation is presented, whereby a laser-pulse of energy below the
breakdown threshold for the host medium, acts to nucleate acoustic
cavitation in a pre-established field. This facilitates the incorporation
of high-speed cameras for interrogation at unprecedented temporal
and spatial resolution, combined with acoustic detection directly correlated
to the observed cavitation activity. A number of cavitation
phenomena are investigated, including bubble-ensemble oscillations at
a very early stage of development, in response to the acoustic driving.
The frequency of oscillation, which bifurcates with increasing intensity,
is also detected in the acoustic emissions. The application of
a single-bubble model predicts a source for the acoustic emissions of
quiescent radius equivalent to the bubble-ensemble observed, for each
intensity investigated. The physical translation of the ensemble, due
to the radiation force imposed by the primary field, is also analysed.
For laser-pulses of energy above the breakdown threshold, applying
focused ultrasound to the cavity promotes and actuates jet-formation.
The characteristics of the so formed jets depend on the intensity and
location of the cavity relative to the ultrasound focus."]},{"key":"dc:title","label":"Title","values":["Cavitation in focused ultrasound"]}]}],"canonical_facts":{"dc:creator":["Gerold, Bjoern"],"dc:date":["2013"],"dc:date.issued":["2013"],"dc:description.abstract":["A novel experimental configuration is developed combining a high intensity
focused ultrasound source and a pulsed-laser, for the study
of cavitation in a field typical of those used for therapeutic ultrasound.
The sonoptic chamber is specifically designed to avoid the formation
of acoustic standing waves, known to have a critical influence
on cavitation behaviour. A new technique of laser-nucleated acous-
tic cavitation is presented, whereby a laser-pulse of energy below the
breakdown threshold for the host medium, acts to nucleate acoustic
cavitation in a pre-established field. This facilitates the incorporation
of high-speed cameras for interrogation at unprecedented temporal
and spatial resolution, combined with acoustic detection directly correlated
to the observed cavitation activity. A number of cavitation
phenomena are investigated, including bubble-ensemble oscillations at
a very early stage of development, in response to the acoustic driving.
The frequency of oscillation, which bifurcates with increasing intensity,
is also detected in the acoustic emissions. The application of
a single-bubble model predicts a source for the acoustic emissions of
quiescent radius equivalent to the bubble-ensemble observed, for each
intensity investigated. The physical translation of the ensemble, due
to the radiation force imposed by the primary field, is also analysed.
For laser-pulses of energy above the breakdown threshold, applying
focused ultrasound to the cavity promotes and actuates jet-formation.
The characteristics of the so formed jets depend on the intensity and
location of the cavity relative to the ultrasound focus."],"dc:identifier":["oai:discovery.dundee.ac.uk:studenttheses/f41bf6b9-ae59-4a41-ba29-d5873821418b","https://discovery.dundee.ac.uk/en/studentTheses/f41bf6b9-ae59-4a41-ba29-d5873821418b"],"dc:identifier.uri":["https://discovery.dundee.ac.uk/files/2189740/Gerold_phd_2013.pdf"],"dc:language":["eng"],"dc:publisher.department":["University of Dundee"],"dc:publisher.institution":["University of Dundee"],"dc:relation.isreferencedby":["https://discovery.dundee.ac.uk/en/studentTheses/f41bf6b9-ae59-4a41-ba29-d5873821418b"],"dc:title":["Cavitation in focused ultrasound"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["Doctoral Thesis"],"dc:type.qualificationname":["Doctor of Philosophy"]},"updated_at":"2026-07-24T02:07:46Z"}